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Conditions and Branching

Comparison​

i = 1
i >= 7 # greater or equals

False

i = 12
i != 10
# != means "not equals"
# -> it's true that 12 isn't = 10

True

  • this goes the same to strings
"kevin" == "ph4n" # this a false
"kevin" != "ph4n" # this a true

True

Branching​

1/ if​

age = 18
if (age > 21):
 
 print('you may drink alcohol')

print("keep it going")

# -> if the statement is False -> it passes to the next

you can't drink alcohol

2/ else​

age = 18
if (age > 21):
    print("you may drink alcohol")

else:
    print("get out")

print("keep it going")

# the system checks if the "if (age > 21)" is true or false -> processes the else
# whether if the if condition is true or false, "keep it going" will still be there

get out keep it going

age = 22
if (age > 21):
    print("you may drink alcohol")

else:
    print("get out")

print("keep it going")

you may drink alcohol keep it going

3/ elif (short for else if)​

age = 21
if (age > 21):
    print("you may drink alcohol")

elif (age == 21):
    print("you may drink it...only this time okay?")

else:
    print("get out")

print("keep it going")

you may drink it...only this time okay? keep it going

Logic Operators​

1/ or​

  • A: False | B: False | A or B: False
  • A: False | B: True | A or B: True
  • A: True | B: True | A or B: True
born_year = 2008
if (born_year < 2000) or (born_year > 2009):
 print("kevinph4n was born in the 90s or 2010s")

else:
    print("kevinph4n was born in 2000s")

kevinph4n was born in 2000s

2/ and​

  • A: False | B: False | A and B: False
  • A: False | B: True | A and B: False
  • A: True | B: False | A and B: False
  • A: True | B: True | A and B: True
born_year = 2008
if (born_year > 2007) and (born_year < 2009):
    print("kevinph4n was born in 2008")

kevinph4n was born in 2008